The steering wheel is always unlocked, and I always look back early in a tow to make sure the front wheels are following in turns. I forgot to unlock the steering on my 1997 TJ once, and it was immediately obvious that something was wrong. I assume the 07 JK would react the same way.
I think the problem is either that the stock BFG MTs are just a substandard implementation of an otherwise great tire or the stock shocks don't measure up. I ran a set of 33" BFG MTs on my 97 TJ and towed it many miles behind my MH without similar wear problems.
I am thinking my next set of tires will be Goodyear Wrangler MTRs and a set of upgrade shocks.